Aluminum anodizing is the process of thickening the layer of aluminum oxide that naturally exists on all aluminum surfaces. This layer has a higher resistance to corrosion and is more porous, allowing it to absorb paints more readily.

Cookware often is treated by anodizing companies to make both conventional and hardcoat anodized products. The process is environmentally friendly although FDA approval depends on the specific aluminum anodizer and process used.

Aluminum anodizing companies can mask certain areas of the part from the anodizing process. This is commonly done with holes. Flat areas that have lettering are more difficult to mask and this is frequently addressed with laser engraving or casting the lettering into the part.

Anodizing companies frequently coat anodized aluminum with chromium compounds to further slow corrosion in a process known as chromate anodizing on aluminum, or chromating. It is especially common in the aircraft industry where the effect of aluminum anodizing and chromating is known as chemical film.

Consider the following points about aluminum anodizing:

1. Buy an anodizing kit with smaller tanks to keep costs at a minimum.
2. Chromating may be even cheaper than anodizing.
3. Coat anodized aluminum with Teflon to create a new market for your products.
   

Action Steps
The best contacts and resources to help you get it done

Compare anodizing kits before starting an anodizing business

Many large studio kits are available that have smaller tanks in the 15- to 70-gallon range and cost much less than the full-size commercial versions. They include the same accessories as the commercial versions, including the filter system with extra filter cartridges, anodes and all the required solutions.

I recommend: Find a variety of anodizing kits at Plating Sales. Caswell Plating specializes in anodizing supplies, especially dyes.

Compare aluminum anodizing and chromating

Chromating does not require that continuous electrical contact be made with the part. This generally means that chromating can be done more quickly and easily than anodizing.

I recommend: Get an estimate from a local aluminum anodizer such as Juracsik Tool and Die that performs both aluminum anodizing and chromating. Aluminum anodizing companies such as Hillock Anodizing offer many finishing services and colors.

Consider coating anodized aluminum with Teflon

Teflon is a popular coating for cookware because it provides a non-stick, non-toxic surface.

I recommend: To get more information on Teflon anodizing, contact Industrial Anodizing. You can find a directory of companies performing Teflon coating in the United States at MFG Quote.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Expect aluminum anodizing projects to require a few days to a few weeks to plan and invoice. Lead times longer than six weeks should be rare.
• •  Understand that Type II anodizing increases the thickness of the aluminum coating by one-third and Type III (hard coat) increases it by one-half. Remember to double these figures when calculating the reduction in diameter of a hole. For example, if a part with a coating that is 0.6 mm thick is subjected Type II anodizing, the thickness of the coating will increase by 0.2 mm. The diameter of a hole will therefore be reduced by 0.4 mm.